This work has been funded in part by NSF, CITRIS, Google and Intel. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Papers

When available, implementations of the code (generally Matlab) and data are linked next to the corresponding paper below.

Vladymyrov, M. and Carreira-Perpiñán, M. Á. (2013): "Entropic affinities: properties and efficient numerical computation". 30th Int. Conf. Machine Learning (ICML 2013), pp. 477-485.
[external link] [paper preprint] [supplementary material] [slides] [video] [poster] [Matlab implementation]The entropic affinities (introduced by Hinton and Roweis, NIPS 2002) are a way to construct Gaussian affinities with an adaptive bandwidth for each data point, so that each point has a fixed effective number of neighbours (perplexity) K. As we show, they can be computed efficiently. They work better than using a global bandwidth for all points in problems such as nonlinear embeddings, spectral clustering, etc.

Carreira-Perpiñán, M. Á., Lister, R. J., and Goodhill, G. J. (2005): "A computational model for the development of multiple maps in primary visual cortex". Cerebral Cortex15(8):1222-1233.
[external link] [paper preprint] [Matlab implementation] [supplementary information]We model the combined development of 5 maps of primary visual cortex (retinotopy, ocular dominance, orientation, direction and spatial frequency) using the elastic net model, as well as the effects of monocular deprivation and single-orientation rearing. We also predict that the stripe width of all maps (orientation, direction, spatial frequency) increases slightly under monocular deprivation. This prediction has been confirmed by Farley et al., J. Neurosci. 2007.

Carreira-Perpiñán, M. Á. and Goodhill, G. J. (2004): "Influence of lateral connections on the structure of cortical maps". J. Neurophysiology92(5):2947-2959.
[external link] [paper preprint] [Matlab implementation] [supplementary information]Using a generalised elastic net model of cortical maps, we show that the number of excitatory and inhibitory oscillations of a Mexican-hat cortical interaction function has a remarkable effect on the geometric relations between the maps of ocular dominance and orientation. We predict that, in biological maps, this function oscillates only once (central excitation, surround inhibition).

Carreira-Perpiñán, M. Á. and Williams, C. K. I. (2003): On the number of modes of a Gaussian mixture. Technical report EDI-INF-RR-0159, School of Informatics, University of Edinburgh, UK.
[external link] [paper] [supplementary information]

Chapter 10 (partially): The acoustic-to-articulatory mapping problem.This contains a review of the acoustic-to-articulatory mapping problem of speech research (the recovery of the acoustic waveform given the vocal tract configuration), emphasising its potential role in improving automatic speech recognition.
[paper PDF] [paper PS]

Carreira-Perpiñán, M. Á. and Renals, S. (2000): "Practical identifiability of finite mixtures of multivariate Bernoulli distributions". Neural Computation12(1):141-152.
[external link] [paper preprint] [Matlab implementation]Mixtures of multivariate Bernoulli distributions are known to be nonidentifiable. We give empirical support to their "practical identifiability" and conjecture that only a small portion of the parameter space may be nonidentifiable. We also give practical advice in estimating the best number of components with an EM algorithm. This conjecture has been recently proven (Allman et al., Ann. Statist. 2009, Elmore et al., Ann. Inst. Fourier 2005): the region of nonidentifiability in parameter space has measure zero for sufficiently many variables.

Carreira-Perpiñán, M. Á. (1996): A review of dimension reduction techniques. Technical report CS-96-09, Dept. of Computer Science, University of Sheffield, UK.
[external link] [paper]Note: this document is out of date. A much more extensive review is provided in chapters 2 and 4 of my PhD thesis.